ctviggen
Well-Known Member
I've been insulating the concrete walls of my basement with Dow Thermax rigid (sheet) insulation. It's the only stuff I found that does not have to be covered in the basement or attic, up to 4 inches thick.
On the "top" surface (near rim joist) of the concrete wall, I added 1 inch of Dow Thermax (can't add 2 inches, as there's only about 1.5 inches there). On the side walls, I've been adding two inches. In the attachments, I show a small, but difficult part of the basement:
I put glue on the "inside" of the sheet, then put the sheet against the concrete, then drill through the sheet and concrete and install a plastic "anchor". The bumps on the picture are the tops of the anchors, covered with tape. I tape all seams and penetrations. I spray foam (with fire-retardant foam) all seams and any penetrations.
The wooden structure (to the left of the ladder) is a temporary structure to support electrical for our solar installation. This is what it looks like after I glued and screwed on some plywood and attached the electrical to the plywood:
That little section of the basement took 7+ weekends, due to the number of wires, electrical that had to be moved, pipe, etc. The whole process has been so time-consuming, it's literally almost divorce-causing.
Here's part I did around an oil tank and on a half wall:
Same thing after taping:
Behind the tank:
Another several weekends for that.
On the other hand, on a quite cold day here in New England, here's the temperature of the cement:
Here's the temperature of the insulation, just to the right of this location:
While this is by far the most time consuming house project I've done, it actually will have a benefit. I just have to slog through the other 30 feet of walls.
On the "top" surface (near rim joist) of the concrete wall, I added 1 inch of Dow Thermax (can't add 2 inches, as there's only about 1.5 inches there). On the side walls, I've been adding two inches. In the attachments, I show a small, but difficult part of the basement:
I put glue on the "inside" of the sheet, then put the sheet against the concrete, then drill through the sheet and concrete and install a plastic "anchor". The bumps on the picture are the tops of the anchors, covered with tape. I tape all seams and penetrations. I spray foam (with fire-retardant foam) all seams and any penetrations.
The wooden structure (to the left of the ladder) is a temporary structure to support electrical for our solar installation. This is what it looks like after I glued and screwed on some plywood and attached the electrical to the plywood:
That little section of the basement took 7+ weekends, due to the number of wires, electrical that had to be moved, pipe, etc. The whole process has been so time-consuming, it's literally almost divorce-causing.
Here's part I did around an oil tank and on a half wall:
Same thing after taping:
Behind the tank:
Another several weekends for that.
On the other hand, on a quite cold day here in New England, here's the temperature of the cement:
Here's the temperature of the insulation, just to the right of this location:
While this is by far the most time consuming house project I've done, it actually will have a benefit. I just have to slog through the other 30 feet of walls.